Examining loneliness and purpose in life as mediators between discrimination and changes in episodic memory in midlife and older adults

OBJECTIVES: Discrimination is a stressor associated with worse cognition, but the pathways underlying this association are unclear. Moreover, discrimination may lead to exclusion and a reduced sense of belonging, which could increase loneliness and reduce purpose in life. We assess whether loneliness and purpose in life are mediators in the relationship between discrimination and episodic memory over an 8-year span. METHODS: Data were drawn from 6,155 respondents aged 51+ in the Health and Retirement Study (2010-2020). Longitudinal lagged structural equation models examined direct effects of (1) discrimination on loneliness, (2) discrimination on purpose in life, and (3) discrimination, loneliness, and purpose in life on episodic memory. Models also assessed the indirect effects of these pathways to test for mediation. RESULTS: Models showed that discrimination and purpose in life were significantly associated with greater loneliness after four years. Loneliness was also associated with reduced purpose in life after a four year-span, but discrimination was not. Loneliness and purpose in life were both associated with episodic memory at follow-up, yet only loneliness served as a significant mediator of the association between discrimination and episodic memory over time. DISCUSSION: Discrimination eroded episodic memory over time, in part due to its effects on psychosocial well-being, in particular loneliness. A reciprocal relationship between loneliness and purpose in life also indicated that discrimination may cause a "negative feedback loop," harming both aspects of psychosocial well-being over time. Findings suggest that interventions targeting upstream determinants of discrimination as well as loneliness may help preserve cognition.